Alternating current (AC) power distribution systems nominally deliver AC electrical power with a root mean square (RMS) voltage between 105 and 135 volts. Generally, RMS voltage delivered at points close to a power generation station is higher than at points further away. The further away points can have generally reduced RMS voltage due to, for example: resistive, inductive, and capacitive losses in the transmission lines between the power generation station and the point of delivery. Additionally, power drawn by devices attached to the line cause additional voltage variations. In jurisdictions where the power line voltages are poorly regulated, power controllers are required to protect electronics such as telecommunications equipment and computers to ensure that the protected devices do not draw more power than they are configured to handle safely. Thus power distribution systems conventionally deliver power that is both systematically variable (due to, for example, relatively fixed configurations of the power distribution system and transmission lines) and sporadically variable (due to, for example, constantly changing power loads drawing from a power grid that change the delivered power over short time periods).
Due to this variability, devices manufactured for operation on AC electrical power are generally configured to operate with a safety margin due to the known variability of supplied power. Devices can be configured to operate from RMS power line voltages between 95 and 135V. Some devices can be configured to operate from RMS voltages as low as 85 V. Devices configured to operate at voltages as low as 85 V waste power when they operate from a power supply of 135 V. Wasted power in such devices is dissipated as heat energy rather than providing useful functioning to the device or to a user of the device. Additionally, device manufacturers must undertake expense to create products that are configured to operate over a broad range of voltages and include components suitable for operation at supply voltages as high as 135 V. Conventional technologies for regulating RMS power delivered by an AC electrical power undesirably generate EMI (electromagnetic interference) and RFI (radio frequency interference) due to rapid switching employed by conventional devices to temporarily remove the load from the power supply and thereby reduce the delivered RMS voltage. In environments with wirelessly connected electronic devices, the existence of RFI creates noise that can disable such wireless devices.
Smart grid technologies are currently being introduced to allow the supply of electricity to be controlled by digital components. Some smart grid technologies provide promise of allowing an electrical power utility or electrical power user to control the time of operation of their electrical appliances according to constantly varying electricity prices, or according available to electrical supply in the grid. Some smart grid technologies allow for a user to program electrical appliances to automatically operate during times when electricity prices are low.